For occasional back pain, over-the-counter pain relievers like ibuprofen or acetaminophen can provide short-term relief. For your knees, clicking sounds (crepitus) are usually harmless unless accompanied by pain or swelling. To support joint and bone health, you can consider supplements like Glucosamine and Chondroitin, Vitamin D3, and Calcium. However, the most effective long-term solution is regular low-impact exercise and stretching to strengthen your core and leg muscles. Please consult a healthcare professional before starting any new medications or supplements to ensure they are safe for your specific health profile.